Scoops or sieves are commonly used for capturing and removing waste from a litter box.
Most scoops are handheld and separate from the litter box. Handheld scoops are used to randomly sift through the litter in search of waste. The person performing removes the waste filled scoop manually from the litter box.
Some scoops are incorporated into a litter box design and are not removable from the apparatus. The scoop may automatically or semi automatically move through the litter pushing the waste. U.S. Pat. No. 5,226,388 describes a litter box and scooping apparatus where at one end of the litter box the bottom curves upward such that scoop pushes the waste up the curve until the scoop is horizontal and will hold the waste independently. The scoop moves into position above a reservoir and then rotates down to deposit the waste. In U.S. Pat. No. 4,048,465 the waste is pushed up the upwardly curved bottom end of the litter box and then falls over the edge of the litter box into a storage reservoir.
Other litter boxes that have non-removable scoops include those where the scoop is fixed to the bottom of a drum shaped container. When the drum is rotated the scoop passes through the litter, capturing and retaining the waste while letting the litter pass through. As drum continues to rotate the waste is guided to a collection assembly and then to a waste reservoir. The waste reservoir can then be removed for discarding waste. U.S. Pat. No. 5,509,379 describes such a device.
U.S. Pat. No. 5,259,340 describes a device where a scoop rotates within a litter box, having a drum shaped interior, and captures waste as it passes through the litter. The scoop stops in a secondary position where waste may drop into a storage container to enable disposal.
Some scoops are incorporated into litter box design but are removable. U.S. Pat. No. 6,295,949 discloses a litter box where waste is captured by a scoop when the litter box is rotated ninety degrees into a secondary position. The scoop is then removed from the litter box and the waste is disposed of.
Other types of scoops include those that rest on the bottom of the litter box. U.S. Pat. No. 5,823,137 discloses a scoop, which rests on the bottom of a litter box and is hingedly attached to the upper lip of one end. This scoop captures waste when lifted upward. As the scoop continues upward, the waste slides down the scoop into storage reservoir. The scoop is not intended to be removed during scooping.
Some scoops contain movable features in order to remove waste from the litter box. U.S. Pat. No. 6,286,459 describes a litter container with rotary movement sieve. A scoop cleans the litter box while vertically oriented and then is hingedly able to horizontally reposition itself as it is removed from the litter box. In the horizontal orientation, the scoop is able to retain waste as it is removed from the litter box.
As litter box design has changed, so have scoop designs. A circular litter box with a rotary sieve or scoop requires new methods for inserting, positioning and removing a detachable scoop.